This invention relates to apparatus for driving nailing plates into the ends of elongate members, such as railroad ties, for the purpose of avoiding or at least minimizing end-splitting and cracking of the ties.
Railroad ties are typically cut from freshly felled trees while the timber is still relatively green. Before being treated with creosote or other wood preservative, the ties are generally permitted to season or dry out for several (e.g., six) months during which time the ties tend to split or crack, particularly at the ends of the ties. If sufficiently large cracks develop, the tie may become unsuitable for use except as for scrap. This of course can be quite costly in terms of low revenue.
There have been attempts to remedy this problem by "end-plating" split railroad ties, that is, by compressing the ties to close the cracks therein and then pressing nailing plates into the ends of the ties to hold the cracks closed. However, prior apparatus have proved unsatisfactory in many respects. For example, the rate at which ties can be end-plated by the apparatus is relatively slow.
U.S. Pat. Nos. 3,419,205 and 3,540,107 show relevant apparatus and method for end-plating ties.